FIG. 6 illustrates a conventional lever connector. Of two connector housings 50 and 60 fitted to each other, a female connector housing 50 has two engagement pins 51 projecting from respective opposite side walls. The male connector housing 60 has two support shafts 61 formed on respective opposite side walls thereof and a lever 62 whose arms 63 extend from both ends of the lever and are rotatably mounted on the support shafts 61.
In connecting the connector housings 50 and 60 together, the female connector housing 50 is inserted slightly into a hood 64 of the male connector housing 60 so that engagement pins 51 enter openings of respective cam grooves 65 formed in the arms 63. With insertion of the female connector housing 50 into the hood 64, a protrusion 52 formed on the underside of the female connector housing 50 and a protrusion 66 formed on the bottom of the hood 64 of the male connector housing 60 move over each other, 25 thereby being engaged with each other. As a result of the engagement of the protrusions 52 and 66, each of the connector housings 50 and 60 is prevented from being moved in a direction in which they come apart from each other. Thus, both connector housings 50 and 60 are held in a preliminary fitted state wherein the engagement pins 51 are located in the respective cam grooves 65, as shown in FIG. 7.
Subsequently, the lever 62 is turned in the above-described state. Both connector housings 50 and 60 are held in the preliminary fitted state such that there is no possibility of disengagement of the engagement pins 51 from the respective cam grooves 65. Accordingly, the lever 62 can be turned smoothly and reliably. By engagement of the pins 51 with the respective cam grooves 65 caused by the turning of the lever 62, the female and male connector housings 50 and 60 are drawn nearer to each other, whereupon both connector housings are connected together in a final fitted state.
As described above, the conventional lever connector employs, as a means for holding both connector housings in preliminary fitted state, a method of engaging the protrusion 52 formed on the underside of the female connector housing 50 and the protrusion 66 formed on the bottom of the hood 64 of the male connector housing 60 with each other.
However, this preliminary engaging means has the following problem. That is, a metal mold for forming a bottom face lying at the rear of the protrusion 66 needs to be drawn out when the protrusion 66 is formed on the bottom of the hood 64 of the male connector housing 60. Accordingly, a mold drawing hole 67 open to the outside of the hood 64 is formed in the inner end face of the hood 64. Consequently, the interior of the connector communicates with the exterior thereof through the hole 67 in the state where both connector housings 50 and 60 are in fitting engagement. There is thus a possibility that water may penetrate into the connector to thereby wet the terminals therein.
Another prior art lever connector will be described with reference to FIG. 16.
Of two connector housings fitted to each other, the male connector housing 170 has two support shafts 171 formed on opposite side walls thereof, respectively, and a lever 172 which is formed into a U-shape and which has plate-shaped arms 173 extending from both ends thereof and rotatably mounted on the support shafts 171 in the same manner as in the foregoing prior art lever connector. The female connector housing has two engagement pins formed on opposite side walls thereof and engaged with cam groove 174 formed in the inner side, faces of the arms, respectively. In the connection of both connector housings, the female connector housing is slightly inserted into the hood 175 of the male connector housing 170 so that the engagement pins enter openings of cam grooves 174 of the arms 173, respectively. Upon turning of the lever 172 in this state, the female connector housing and the male connector housing 170 are drawn nearer to each other by the engagement of the engagement pins with the respective cam grooves 174 caused by the turning of the lever 172, thereby being connected together.
In the above-described lever connector, an excessively large torque is applied to each arm 173 when the lever 172 is turned. Accordingly, the arms 173 tend to be flexed outwardly such that the engagement pins are disengaged from the cam grooves 174, respectively. If the arms 173 should be flexed outwardly, they would be disconnected from the respective support shafts 171. In view of the this problem, falling-off preventing walls 176 are provided on the outer side faces of the male connector housing 170 for preventing the arms 173 from being flexed and falling off of the support shafts 171.
Each conventional falling-off preventing wall 176 has a portion extending outwardly from the side wall of the male connector housing 170 in the shape of a plate, the portion being bent so as to face the outer face of the arm 171, as shown in FIG. 7. When the arm 173 is flexed outwardly, the inner face of the falling-off preventing wall 176 is caused to abut against the outer face of the arm 173, thereby preventing the arm 173 from being flexed outwardly and consequently preventing the falling-off of the arm 173 from the support shaft 171.
However, each falling-off preventing wall 176 is located outside the arm 173. This increases the width of the male connector housing 170. Consequently, the connector cannot be mounted, or the mounting work is rendered difficult when a mounting space for the connector is small, or when there is some limitation in the mounting location or direction of the connector. This problem occurs in the case where the lever is mounted on the female connector housing as well as on the male connector housing.